Abstract The concept of the spatial wettability gradient is applied to bulk porous media to passively influence directional spontaneous imbibition flow. The imbibition process in an oil-bearing medium was mathematically modeled and experimentally validated for cores with an induced wettability profile. This was modeled by defining a wettability capacity distribution function (WCD), which is incorporated into the capillary forces term in the transport equation. The performance of the model was verified via experiments varying the interfacial tension, viscosity, permeability, core size, and porous materials. Gypsum, calcite, and hydromagnesite exhibited specific displacement patterns under one-end-open and two-ends-open boundary conditions. Of these materials, calcite and gypsum showed a symmetric saturation pattern. In contrast, hydromagnesite was the only material that exhibited a directional phase displacement under a two-ends-open boundary condition. This behavior has been associated with a WCD. The mathematical model accurately predicted this behavior, reflecting that the main interacting forces have been considered.

中文翻译：

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通过多孔结构中的自发水吸收定向置换非水流体

摘要 空间润湿性梯度的概念应用于多孔多孔介质以被动影响定向自吸渗流。含油介质中的渗吸过程对具有诱导润湿性分布的岩心进行了数学建模和实验验证。这是通过定义润湿容量分布函数 (WCD) 来建模的，该函数被合并到传输方程中的毛细管力项中。通过改变界面张力、粘度、渗透率、核心尺寸和多孔材料的实验来验证模型的性能。石膏、方解石和水菱镁矿在一端开放和两端开放的边界条件下表现出特定的位移模式。在这些材料中，方解石和石膏显示出对称的饱和模式。相比之下，水菱镁矿是唯一在两端开放边界条件下表现出定向相位移的材料。此行为已与 WCD 相关联。数学模型准确地预测了这种行为，反映了主要的相互作用力已经被考虑在内。